HYDRAULIC SYSTEM and REACTION UNIT SERVICE n Chapter 5 n Page 98 n Lab manual

DIAGNOSE HYDRAULIC and VACUUM CONTROL SYSTEMS n The best way to identify the exact cause of transmission problems is to use the results of a road test: n Logic n Oil charts circuit charts for the transmission being worked on. Page 98

PRESSURE TESTS n If the road test does not find the problem, perform a pressure test. n Check minimum line in all ranges. n Check maximum line in all ranges. n What does that mean? Page 99

TESTCHART TESTCHART

VALVE BODY SERVICE n Drain transmission. n Remove valve body disassemble halves check for stuck valves. n Do NOT remove valves until you have found the problem. n Use a Polaroid camera for check ball location. Page 105

CLEANING AND INSPECTION n Individual VB parts are not sold separately. n Use spray carb cleaner, WEAR EYE PROTECTION. n Place unlubricated valve in its bore, hold vertical it should fall out by its own weight. Page 107

VALVEBODY REASSEMBLE n Use notes. n Photos n Manuals n Place valve body gaskets over separator plate, Gasket can NOT cover any holes in plate. n DO NOT OVERTIGHTEN VB BOLTS. Page 110

GOVERNOR SERVICE n If diagnostic road test indicates a governor problem. n Remove, disassemble, clean, and inspect. n Two main types of governor problems, –Late shifts –Not starting in first gear from a stop. Page 111

DISASSEMBLY n Most governors have a Primary and Secondary valve. n Valves should be free to move from their own weight. n Inspect drive gear, if it has one. n Clean thoroughly. Page 112

REASSEMBLY n Do not mix up primary and secondary weights or springs. n Install valves correctly, see fig n If governor pressure gauge reads less than 2 PSI ValveBody problem. n If governor pressure gauge reads more than 2 PSI Governor problem. Page 112

OIL PUMP SERVICE n The oil pump should be carefully inspected during overhaul, especially if Trans had low line pressure. Page 113

DISASSEMBLY n Note position and direction of pump gears before removal. n Look at P5-5, P5-6, and P5-7. Page 114

INSPECTION n Inspect the pump bore for scoring on both its bottom and sides. n A front pump bushing with two much clearance will allow gears to run off center. n Check stator splines for wear. n Check all bushings for wear and size. n Check halves for warpage. Page 116

REASSEMBLY n Pump bushing and seal should be installed with proper driver. n Lube bushing and seal lip. n Coat pump gears in Trans fluid before assembly. n Use proper tools to align pump halves. Page 118

BAND SERVICE n Single or double wrap designs. n Cast iron or flex type. n Do not flatten out flex band or lining may crack. Page 119

INSPECTION n Look for chipping, cracks, burn marks, glazing, nonuniform wear patterns, and flaking. n The drum surface should be checked for discoloration, scoring, glazing, and distortion. n Cast drums should be sanded with 180- grit sandpaper. n The surface of the drum should be flat, check all stamped drums.

BAND ADJUSTMENT n Every band must be adjusted when installed. n Some transmissions do not require periodic band adjustment. n Some use adjusting screws, and some use selective apply pins. n The timing of the band application has a lot to do with how the shift feels. page 120

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SERVO and ACCUMULATOR n Some servos are serviceable in the car. n Some accumulators are serviceable in the vehicle. n One of the main problems are leaks. n Check bores for gouges and scoring. page 122

ACCUMULATORS n Remove accumulator cover snap ring. n Remove cover, piston and spring. n Be sure to note order of disassembly. n Manuals may have poor pictures. n Piston in first or spring in first? n Check seals rubber, Teflon, or steel. page 122

SERVOS n A servo is connected to a band. n Same checks as for a accumulator. page 123

SEALS n Most original equipment servo seals are of the Teflon type. n Cast iron hook ring may be supplied as replacements. n Be sure to check ring size in the bore it goes in. n Check that the ring are free in ring groves. page 124

INSPECTION Page 124

ASSEMBLY Page 124

SELECTIVE APPLY PINS Page 124

CLUTCH PACKS n Two types of clutch packs: n Rotating drum-Case grounded n All clutch plates are held in place with snap rings, with some selective thickness. n There may be two or more snap rings of the same diameter but different thickness or shape. page 126

DISASSEMBLY n Remove snap ring retaining the pressure plate. n Remove friction and steel plates. n Use clutch piston spring compressor to compress spring and remove snap ring. n Remove retainer, springs, and piston. n Note direction of seal installation. page 127

INSPECTION AND CLEANING n Make sure that you keep the parts of each clutch separate. n Clean all parts, and air dry. n Check all splines. n Check retainers and springs. n Check wave plates for scoring, height. n Check ring groves, bushings on drums. page 132

CLUTCH PACK REASSEMBLY n Install new seals and lube before installation. n Soak frictions in ATF prior to installation. n If clutch has a belleville spring the lower pressure plate must be rounded on the bottom side. page 135

CLEARANCE CHECKS n Adjust clearance by: –Selective snap rings –Selective pressure plates –Selective apply rings –Oversize steel plates n Non shifting clutch packs have less clearance than shifting clutch packs. n Clutches with Belleville spring.025 max. page 139

AIR TESTING n Check with drums on pump and, n Check before valve body is installed. page 140

ONE-WAY CLUTCHES n The durability of these clutches relies on constant fluid flow during operation. n If failure has occurred trace lube circuit and verify volume and pressure. page 141

ROLLER CLUTCHES page 142 n Check rollers for roundness. n Check springs for distortion. n Check races for any irregularities. n One spring for each roller. n Sand races with a crosshatch pattern. n Check for correct direction of operation.

SPRAG CLUTCHES n Sprag element can not be disassembled. n If an element falls out replace the sprag. n Check races for any irregularities. n Sand races with a crosshatch pattern. n Check for correct direction of operation. page 142

TRANS COOLER SERVICE n Flush cooler at time of overhaul. n Check lines for leakage. n Check for rubbing on pan, crossmember, etc. n If the fluid can not circulate, it can not cool. n Some radiator Trans coolers have internal filters. page 142

CASE STUDY n Understand basic theories. n Listen to everyone. n Believe no one. n Prove it to yourself.